Dipper door control



May 30, 1939. VIDAVIDSON 2,160,432

DIPPER DOOR CONTROL Filed June 28, 1938 3 Sheets-Sheet l In ventor Varzsflam' 623072.

A ttorneys y 30, 1939- v. DAVIDSON 2,160,432

DIPPER DOOR CONTROL I Filed June 28, 1958 3 Sheets-Sheet 2 Jay-f Inventor yai'zlffldw'daoiz,

May 30, 1939.

v. DAVIDSON DIPPER DOOR CONTROL 3 Sheets-Sheet 3 Filed June 28, 1938 A itomeys Patented May 30, 1939 DIPPER D Voris Davidson, Lyons,

0R CONTROL 7 Ind., assignor of one-half to George P. Buzan, Lyons, Ind.

Application June 28,

4 Claims.

The present invention relates to shovelsand more particularly to a control for the dipper door thereof.

l'n'power shovelsthe door is secured to the dipper by suitable latch mechanism to close it while the dipper is receiving or carrying its load, and is allowed to swing free during the discharge of the load. Frequently the dipper door is rapidly opened and shut as in the shaking of the dipper during discharge operations and repeated contact of the door against an unyielding part of the shovel structure results in dam-age to the part and eventual depreciation and breakage.

It is accordingly an object of the present invention to provide a simple and efficient construc tion for restricting the free swinging movement of the door, the invention embodying essentially a plurality of friction drums at the pivot of the door for the aforesaid purpose.

Another object is to provide an apparatus of this character of simple and practical construction, which embodies means for adjusting the friction control means and to generally provide an apparatus of this character which is well adapted for the purposes for which the same is intended.

Other objects and advantages reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming part hereof, wherein like numerals refer to like parts throughout, and in which:

Figure 1 is a sideelevational view of the dipper.

Figure 2 is a top plan view.

Figure 3 is an end elevational view.

Figure 4 is an end elevational view of one of the friction drums and associated mechanism.

Figure 5 is a sectional view through one of the drums taken substantially on a line 5-5 of Figure 2.

Figure 6 is a sectional view taken substantially on a line 65 of Figure 2.

Figure 7 is a rear elevational view of one of the brake shoes, and

Figure 8 is a detail of one of the lubricating shafts.

Referring now to the drawings in detail, wherein for the purpose of illustration I have disclosed a preferred embodiment of the invention, the numeral 5 designates a dipper generally having the usual supporting arms 6 and provided at its rear with a conventional type of door 1 having a plurality of arcuate arms 8 extending upwardly and over the top of the dipper and pivotally at- 1938, Serial No. 216,359

tached thereto as at 9 to provide for the free swinging movement of the door. I 7 i v To the top of the dipper is fixedly secured a pair of L-shapedplates l0 having-their upstanding portions ll secured to opposite sides of a plate 12 rising from the top of the dipper and bolted thereto as at [3. From the base portion of the plates or brackets I0 rise bearing brackets l4, within which one end of a pair of shafts l5 are supported, the opposite ends of the shafts being supported by the upstanding portions ll of the brackets ID as will be apparent from an inspection of Figure 6 of the drawings.

Freely rotatable on each of the shafts I5 is a drum l6, having a bushing l1 interposed between the drum and shaft, and spacing washers l8 positioned between the opposite sides of the drum and the adjacent supporting structure. The shafts I5 are secured in position by keys l9.

Pivotally mounted in brackets 20 are a pair of brake arms 2| having their upper ends terminating in spaced relation at the top of the drum and connected by an adjusting rod 22, one end of the rod being provided with a coiled spring 23 positioned between one of the arms and a head 24 on the rod. Brake shoe 25 is provided with a lug 26 pivotally attaching the same as at 21 to an intermediate portion of each of the arms 2|, said brake shoes being positioned in frictional en gagement at opposite sides of the drum IS. A brake lining 28 may be provided for the drum, if desired.

One end of an arm 29 is bolted to one side of each of the drums Hi, the opposite end of the arm being pivotally connected to one end of a link 30 which has its opposite end pivotally connected to one end of an arm 3| which has its opposite end fixedly secured to the door 1.

Brace blocks 32 are secured to the side of the drum in engagement with opposite sides of the arm 29 to rigidly support the same.

The shafts l5 may be provided with ducts 33 extending outwardly through the ends of the shafts and to which a grease fittingmay be attached for lubricating the bushings ll.

In the operation of the device it will be apparent that the nut 24 is adapted to place proper tension on the spring 23 to maintain the brake shoe 25 in frictional engagement with the drums l6 and by reason of the connection of the drums with the door 1 through the arms 29, links 30 and arms 3|, the free swinging movement of the door is properly restricted.

It is believed that the details of construction and manner of operation of the device will be readily understood from the foregoing without further detailed explanation.

Having thus described the invention, what I claim is:

1. In a dipper door control apparatus, a dipper having a door swingably carried thereby, a drum rotatably carried by the dipper, friction means restricting movement of the drum and a linked connection between the drum with the door and including rigid members fixedly attached to the drumand door and a rigid connector pivoted to each of said fixed members.

2. In a dipper door control apparatus, a dipper having a door swingably mounted thereon, a drum rotatably carried by the dipper, brake shoes for the drum, means yieldably urging the shoes into frictional engagement with the drum and a. linked connection between the drum and the door to restrict free swinging movement thereof and including rigid members fixedly attached to the drum and door and a rigid connector pivoted to each of said fixed members;

3. In a dipper door control apparatus, a dipper having a door swingably mounted thereon, a

drum rotatably carried by the dipper, brake shoes for the drum, means yieldably urging the shoes into frictional engagement with the drum and means connecting the drum to the door to restrict free swinging movement thereof, said last named means comprising arms fixedly attached to the drum and the door and a link pivotally connecting said arms.

4. In a dipper door control apparatus, a dipper having adoor swingably mounted thereon, brackets carried by the dipper, a plurality of drums rotatably supported by the brackets, a pair of brake shoes for each of the drums pivotally mounted at one end, means yieldably connecting the free ends of the shoes for urging the shoes into frictional engagement with the drums and means connecting each of the drums to the door to restrict free swinging movement of the latter, said means comprising an arm fixedly secured at one end to the drum, an arm fixedly secured at one end to the door and a link pivotally connecting said arms.

VORIS DAVIDSON. 

